Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation (Summary Of Stock Compensation Expense) (Details)

v2.4.1.9
Stock-Based Compensation (Summary Of Stock Compensation Expense) (Details) (USD $)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]    
Share Based Compensation $ 608,795us-gaap_AllocatedShareBasedCompensationExpense $ 565,428us-gaap_AllocatedShareBasedCompensationExpense
General and administrative [Member]    
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]    
Share Based Compensation 457,128us-gaap_AllocatedShareBasedCompensationExpense
/ us-gaap_IncomeStatementLocationAxis
= rnn_GeneralAndAdministrativePayrollMember
503,076us-gaap_AllocatedShareBasedCompensationExpense
/ us-gaap_IncomeStatementLocationAxis
= rnn_GeneralAndAdministrativePayrollMember
Research and development [Member]    
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]    
Share Based Compensation $ 151,667us-gaap_AllocatedShareBasedCompensationExpense
/ us-gaap_IncomeStatementLocationAxis
= rnn_ResearchAndDevelopmentConsultingAndOtherProfessionalFeesMember
$ 62,352us-gaap_AllocatedShareBasedCompensationExpense
/ us-gaap_IncomeStatementLocationAxis
= rnn_ResearchAndDevelopmentConsultingAndOtherProfessionalFeesMember